Quantification of acrosclerosis: Measurement of skin thickness and skin-phalanx distance in females with 15 MHz pulsed ultrasound

Abstract

The skin thickness of the extensor and flexor aspects of the forearm (TEF, TFF), and the skin-phalanx distance over the middle and proximal phalanges (DMP, DPP) were measured with a 15 MHz ultrasound (A-scan) apparatus. Twenty-two females with systemic sclerosis (acrosclerotic type) and 22 healthy females matched for age were studied. DMP, DPP, TEF and TFF measurements were all increased in systemic sclerosis (p < 0.001, p < 0.001, p < 0.01, p < 0.02). Standards for normal skin-phalanx distance and skin thickness in females were defined (mean ± 2 SD). DMP and DPP were not correlated to age in the controls. TEF and FEF decreased slightly with age, 0.078 and 0.062 mm/10 years of life respectively. DMP was increased in 18 (82%), DPP in 13 (59%), TEF in 7 (32%) and TFF in 5 (23%) patients with systemic sclerosis, as compared with standards defined. Non-invasive measurement of skin-phalanx distance of the digits and skin thickness of the forearm with high-frequency ultrasound is concluded to be poorer for the diagnosis of acrosclerosis and for quantification of sclerodermatous skin changes during medical treatment.